*glass, that container who you usually use to drink water. In Mexico a *glass can be made of plastic, glass or foamed polystyrene... it only needs to have a glass shape to be called glass no matters the material is made of, but in English a glass is still a glass if is not made of glass?


I wouldn't be so sure of this. I often hear people speak of 'plastic glasses'. Sometimes, they are translucent, sometimes not.

If someone asks me if I'd like a glass of water, I may receive it in something that is not made of glass.

I think that in practice, it's often a subtle matter that may involve the shape, the material, the contents, and possibly even the context.

Best wishes, Clive
Yes, it is a glass even if it is not made of glass.

Hope this helps.

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A cyberfriend from USA told me that if a glass is not made of glass then must be called "cup"! That container fill of soda that you get in a cinema is called "glass"?

For and this would you say "plastic glasses"... or?
I agree with your friend. Here in the U.S., a drinking cup is called a glass only if it's actually made of glass, regardless of shape. Otherwise, it's called a cup.
 Clive's reply was promoted to an answer.
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